Jeepers Peepers

Some folks swear by a spring tonic to wake up from winter’s torpor. How about a tonic for the ears? The call of spring peepers is a piercing, ringing chorus that rises from wetlands to permeate the soundscape—an alarm clock with no snooze button. That high-pitched peeping might be mistaken for a bird’s, but spring peepers are tiny frogs, 3/4- to 1 1/4-inch long (females are larger than males), with big brown eyes and skin in brown hues that change to match their surroundings. Their scientific name, Pseudacris crucifer, refers to a dark X-shaped mark on their back.

 

Peepers are terrestrial, living in woods and swamps. They can climb trees and plant stems, using toe pads. They are typically nocturnal outside the breeding season. They eat small invertebrates and, in turn, are preyed upon by snakes, turtles, birds, and small mammals.

 

Over the winter, peepers hibernate, burrowed under logs or leaves. They produce a natural anti-freeze that circulates in their blood. When the air is consistently warm—usually late March to early April when temperatures hit the mid-40s—peepers congregate in marshes, ponds, stream edges, and even roadside ditches, where there’s long-stemmed vegetation and nearby trees.

 

Sitting up on his calling station—a plant or mud pile—a male peeper peeps by squeezing air from his lungs over his vocal cords into a balloon-like throat sac, creating a resonating chamber that amplifies the peep to a PEEP! Males call thousands of times an hour, day and night. Besides the peep, they also emit a trill to warn off competitors edging into their territory.

 

Peepers are so small and well-camouflaged that you’re unlikely to see one even up close, and if you’re that close you might be too close for comfort: The call has been measured at ninety decibels, as loud as a motorcycle. It can be heard a half-mile away. Any female peeper within that distance knows where to head if she likes the sound.

 

Females do not call. Not all males call, either: Some freeloaders intercept the females attracted by callers. Once a pair mates, the female deposits 800 to 1,000 eggs, which are placed singly on aquatic vegetation or in debris on the bottom of ponds.

 

The peeping season usually lasts several weeks, through April and even May. Afterwards, the frogs disperse. Spring peepers can be heard calling, though less vigorously, in autumn, as spring-like day length and temperature trigger hormonal responses. This vocal phenomenon is known as the “fall echo.”

 

Spring peepers, abundant in the River Towns, can be heard in many parks and nature centers. Check out Tyler State Park’s Scenic Loop or the D&R Canal towpath. Bucks County Audubon’s Honey Hollow Nature Center, in Solebury, offers an evening “Frog Walk” in late March. Unlike an alarm clock, the wake-up call of the spring peeper is something to look forward to.

 

Susan Charkes is the author of The Wild Here and Now (Arboreality Press, 2013), a book of nature essays whose front cover is graced with a portrait of a spring peeper. More at susancharkes.com.